Don't try to remove a secondary interrupter that is known to be invalid. Also check if the interrupter is valid inside the spinlock that protects the array of interrupters. Found by smatch static checker Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Closes: https://lore.kernel.org/linux-usb/ffaa0a1b-5984-4a1f-bfd3-9184630a97b9@moroto.mountain/ Fixes: c99b38c41234 ("xhci: add support to allocate several interrupters") Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx> --- drivers/usb/host/xhci-mem.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c index 4460fa7e9fab..d00d4d937236 100644 --- a/drivers/usb/host/xhci-mem.c +++ b/drivers/usb/host/xhci-mem.c @@ -1861,14 +1861,14 @@ void xhci_remove_secondary_interrupter(struct usb_hcd *hcd, struct xhci_interrup struct xhci_hcd *xhci = hcd_to_xhci(hcd); unsigned int intr_num; + spin_lock_irq(&xhci->lock); + /* interrupter 0 is primary interrupter, don't touch it */ - if (!ir || !ir->intr_num || ir->intr_num >= xhci->max_interrupters) + if (!ir || !ir->intr_num || ir->intr_num >= xhci->max_interrupters) { xhci_dbg(xhci, "Invalid secondary interrupter, can't remove\n"); - - /* fixme, should we check xhci->interrupter[intr_num] == ir */ - /* fixme locking */ - - spin_lock_irq(&xhci->lock); + spin_unlock_irq(&xhci->lock); + return; + } intr_num = ir->intr_num; -- 2.25.1
